Folkinfo is worth visiting even if Mudcat is up and running. It tends to have less trivia than the cat, but is a good resource for traditional song and tunes. Jon and some other members (often also mudcatters) have been trying to get accurate references (earliest printed copy, documented recordings etc.) attached to songs and tunes posted there.
He also has collections of tunes in ABC format.
Quack!
GtD.